Air engine



4 Sheets-Sheet 1 F- S. BARKS March 5, 1929,

AIR ENGINE Original Fled Dec. 3, 1925 Kxxm. K n @www @www F. S. BARKSAIR ENGINE March 5," 1929.

Original Filed Dec. 3, 1925 4 Sheets-Sheet March 5, 1929-. F 5 BARKS1,704,238

AIR ENGINE original Filed Dec. 1925 4 sheets-sheet 5 F. 5. BARKS AIRENGINE March 5, 1929.

Original Filed Dec. 5, 1925 4 Sheets-Sheet Litl Patented Mar. 5, 1929.

. UNITED STATES 1,704,238 PATENT oFFlcE- FRANK S. .'BARKS, 0F ST.LOUIB,MISS0URI.

In ENGINE l Original application led December 3, w/Serial No. 72,898.Divided and this application led June 28, 1926. Serial No. 119,118.

This invention relates to air engines or motors, and with regard tocertain more speciiic features to an air engine for operating a portablegrease pump or the like.

This application is a division of the invention set forth in my patentapplication on a lubricating device, Serial No. 72,898, led December 3,1925.

Among the several objects of the invention may be noted the provision ofa portable grease pumping engine which is instantly operable to pumpquantities of grease merely upon manual operation of a valve; theprovision of a pneumatic grease pumping engine which is adapted toreceive air tor operation from the ordinary pneumatic tire iilling airline and valve; the/` lrevision ot apparatus of the class describedwhich pumps predetermined quantities of *l grease; the provision ofapparatus of the class described comprising in part an improvedhill-stroke valve gear and cooperating seli3 y oi': a device of theclamss described which is economical of manufacture, light in weight,yet subject to little or no derangement in operation. *Other objectswill be in part obvious and in part pointed out hereinafter.

The invention accordingly consists oit' the i eiements and combinationof elements, features oi construction, and arrangements of parts whichwill be exemplified in the structure hereinafter described and the scopeof` the application of which will be indicated in the following claims.

In the accompanying drawings, n which is shown one of various possibleembodiments of the invention,

Fig. 1 is a top plan view of the apparatus,

showing parts broken away;

Fig. 2 is a longitudinal vertical section taken on line 2 2 of Fig. 1;

Fig. 3 is a rear elevation of, the device showing certain parts brokenaway;

Fig. 4 is a vertical lateral section taken on line 4-4 of Fig. 2; and

Fig. 5 is a diagrammatic plan view showing in solid lines thearrangement of vari ous parts while yin use, and in dotted lines showsthe arrangement of .certain parts when the device is not in use.

Similar reference characters indicate cor-y responding parts throughout`the several views of the drawings.

aligning device; and the provision Referring now more particularly toFigs. l and 2 of the drawings, there is illustrated at numerals 1 and 3,a pair of longitudinal with a swivel caster 7.' The casters 7 areadapted to stay with the legs 5, when the device is picked up as will behereinafter described.

The rails 1 and 3 are provided with upper horizontal flat machinedsurfaces 9 for the purpose of receiving bolted thereto, at the forwardends, a laterally formed pump casting 11. Rearwardly the surfaces 9 ofthe frames 1 and 3 have bolted thereto a laterally formed engine casting13. The frames 1 and 3 and castings 11 and 13 form a unit. Forstiffening purposes a cross-bolt 14 and spacer 16 .(Figs. 1 to 3) areprovided laterally between andv centrally of the side frames. This,stidening device may be dis- -pensed with in small sizesot the pump.

Between the castings 13 and 11 and rails 1, 3 respectively, are heldbolted sidewardly extending oppositely placed horns or hose clips lforthe purpose of holding cradled therein the delivery line when not inuse, as will be further made clear. V

Held also to opposite sides of said castings 11 and 13 is a handle orgrip 17 by means of which the greasing device as a whole may be liftedand transported about.

Bored lugs or ears 19 on the rear of the side frames 1 and 3 are adaptedto rotatably receive a forgedhandle-bar 21 for purposes of drawing thepump about. The handlebar 21 is forged with downward extensions 23 whichengage a pair of the said legs 5 of the rails 1 and 3 and preventdescent` of the bar to the door when said bar yis not in use (see Figs.2 and 5);

Referring now more particularly to the forward pump casting 11, it maybe seen that said casting includes anges 25 whereby it is bolted to thesideframes 1 and 3, as described. Longitudinally and centrally of saidianges and formed 'therewith is a bored plunger cylinder 27 provided atits forward end with a. conventional ball check valve 29. As indicatedin Fig. 2, the rear end of said plunger cylinder is formed 4as a. piainslide bearing 33. Around a more or less central portion of .andrecrosses the space 35.

vided with a lid 41. The bottom 43 thereof is provided with` an opening45 which aligns with the upper opening of the chamber 37 and is adaptedto receive the conical rim of a strainer 47 therein.

Now, as will later be made clear, grease and the like is adapted to bedrawn or forced from the container, through the strainer 47, passages37,. 35, borev of cylinder 27, valve 29, to a supply line 49 (preferablyflexible) made fast to the outlet end of the valved cylinder 27.

To accomplish the above purpose, a plunger 51 is caused to reciprocatein the bored cylinder 27 so that its forward end crosses The plunger ismade to fit the cylinder 27 snugly and as J the plunger recedesrearwardly, the check valve 29 automatically closes. Hence, a vacuum isdrawn in the cylinder 27 and as the plunger end recedes over the more-or less annular opening 35, grease rushes from all sides of thecylinder 27 and into said cylinder. At the next forward movement of theplunger the grease in cylinder 27 is forced through the cheek valve 29and out into the line 49. In starting the device, it may be primed bypouring oil into the passages 35 by way of the container 39. If after laperiod of operation the device should lose it prime, priming may beaccomplished by inverting said device, removing a plug leading tochamber 35 and pouring oil or the like into said chamber 35. This lattermethod of priming savesvthe operation of removing grease fromv'thecontainer f39 in order to get oil into the passage 35.y

It is clear that the reciprocating action of the plunger 51 may becontinued indefinitely to draw grease from .the container 39' anddischarge it into line 49. In order to reciprocate the plunger, an airengine E is provided at the rear of the device. This engine isassociated with, and cast (in part) with the said casting 13.

rlhe air engine E comprises a work cylinder 55 to which islongitudinally cast, on center line, a spring retaining cylinder 57.These cylinders are adapted (as a unit) to be aligned on center linewith the cylinder 27, at least approximately.

Passing through the cylinder 57 and into cylinder 55 is a piston rod.59. The rod 59 passes out of the forward end of said cylinder 57 andcooperates with the vplunger 51 by means of a counter bore and cross pincombination 61. The combination 61 is permarient but during assemblypermits of some mis-alignment between the cylinders 55, 57 and 27, in sofar as the counterbore in the shaft 59 may be made somewhat larger thanthe diameter of plunger 51.

At the rear end, the rod 59 is provided With :a driving piston 63. Thepiston comprises a backing plate 65, a leather piston 67 and a clampingcup 69, all held to a shoulder on rod 59 by meansof' a nut as shown. Thecup 69 is flanged out farther than is the piston, so that the relativelysoft piston can not strike the head 71 of the cylinder 55. The piston 63is normally held moves with the piston rod 59. It isso supported for thesaid movement by screwing the rear end of it into the piston 63 andpinning the forward end into aV vertical bracket 77, which bracket isheld by means of a tight lit, and set screw 79 to the forward jointedend of t-he piston rod 59. The said rod 75 slidably passes through aproper passage in thehead end of the cylinder 55 and is steadied bypassage through an ear 81 at the front end of the cylinder 57. It`

is clear that by means of the construction described, the piston rod 59can not twist out of its assembled position and a rugged aligning systemis, provided for driving the valve gear to be described.

A crossshaped lug 83 is east on the top of the work cylinder 55. The lugis provided*- with a longitudinal bore 85 for slidably receiving a valve87. Positive movementlimiting heads 89 and 91 are provided at the isinterposed between the valve 87 and the interiorgof cylinder 55. T heexhaust passage 97 leads direct to the atmosphere and the inlet passageis provided with a conventional air inlet plug 103.

To bring air to the inlet passage 95 it is only necessary to hold aconventional air nozzle (such as is used for filling automobile tiresand available at most garages) to the plug 103. The plug 103 and nozzle105 mutually open one another and air may flow from the compressed airline 107, associated with said nozzle 105, to the inlet passage 95. Thedescription of the plug 103 and nozzle 105 is not detailedhere, inasmuchylil as their constructions and combinations are well known,conventional, and are not claimed herein to be new per se.

ln order to hold the nozzle 105 to the plug 103, a hinge block 109 isheld to the lug 83 by means of a shoulder on the plug 103. To this block109 is hinged an adjustable saddle member 111, 'which is adapted toswing over ily be removed by lifting, and whence air automaticallyceases to flow from the nozzle 105, or to tend to flow into the passage95.

Returning to the valve construction, the drawings (Fig. 2) show that thevalve 87 is provided with a groove 115 adapted to register with the saidinlet passage 95 and outlet passage 97 when the valve is in its maximumrearward and forward positions respectively. Hence, by positioning thevalve 85 rearwardly,ithe exhaust passage 97 is closed, while the inletpassage 95 is opened whereby compressed air 'may pass from the line 107through the open nozzle 105, open plug 103, passage95 and groove 115,passage 101, passage 99 and to the cylinder 55, where l work' is done topress the piston 53 forwardly against the action of spring 73. By thismeans' the plunger 51 is made to takea grease forcing stroke ashereinbefore described. lient, hy positioning the valve 85 forwardly,the groove 115 aligns with the exhaust passage 97, as shown in Fig. 2,whereupcn the inlet passage 95 is `closed. This action permits movementof air from the cylinder through passages 99, 101, 97 and groove 115.Such movement of air is caused by the tendency of the air. to re'expandand the arpa-riding action N'of spring 73 which pushes the piston 03rearwardly. The port 99 is near the. bead 71 so that the cylinder 55 maybe substantially emptied of air.

Movement of the piston 63 and rod 59 rearwardly results in an evacuatingstroke of plunger 51, whereby the grease cylinder 27 is again reloadedas hereinbefore described. l

In order to automatically position the valve 85 at its said maximumforward and rearward positions, so that pumping may be continuous whendesired, the following fullstroke mechanism is used:

1Vertically fastened to the driving rod 75 is fastened a driving bracket117 adapted to slidably engage the valve stem 93. Springs 119 and 121are placed over said stem 93 rearwardly and forwardly respectively.These springs 119 and 121 respectively engage the said head 91 andanother head 123 of the stem 13. Thel bracket 117 engages the springs inits travel back and forth along Vthe passages 95 and 97.

the stem 93. It is clear that upon engaging and compressing a spring toa given point, that the driving bracket (moving with the piston rod 59)will drive the valve rod 93.

In order to prevent the valve 87 from moving to reverse agiven stroke ofthe pis t0n G3 before the stroke is substantially finished, regardlessof the predetermined length of said stroke, and to cause said valve t0take a full stroke at every 'movement thereof, it is recessed at points125 and 127. Corresponding points on the recesses area distance apartequal to the distance between Formed preferably horizontally across thevalve passage 85, at a point corresponding to the position of recess 125when the valve 87 is in forward position, isa passage 129 (see llig. 4).On each side of the valve 87 in the recess 125 is placed a ball 131. Theballs are each backed by a compressed spring133 reacting against aretaining plug 135. llly this means the valve 87 may be resiliently heldin either its exhaust or inlet position, depending upon which recess1257er 127, the balls 131 are cooperating with.

lWhen the driving bracket 117 moves against the spring 119 (Fig. 2) andsubstan tially compresses it, the rearward motion of the pist-on 63 isadapted to be aboutcom` pleted. In the meantime theorecess 125 and'balls 131 have caused the valve87 not to be moved, despite the partialcompression of spring 119. Finally at or near the end of the stroke ofpiston 63, the spring is adapted to have been compressed enough toovercomethe holding power ofthe balls 131, and the valve 87 moves underaction of the 'spring 119. The valve must move rearwardly its fullstroke` because, as the high ridge 137 between the recesses 125 and 127passes the balls 131, the inward movement of the balls into the recess127 forces the valve to full stroke position as described, although thespring 119 may by this time have expanded to such a position that itwould not, without'the full stroke feature, be able to move the valve toa position such that the groove 115 aligns with port 95. Of course, asthe valve opens the inlet air port 95, the motion of the piston isreversed to a forward direction, and reversal of the above events takesplace. This time., however, the spring 121 comes into play, while spring119 is idle. The reverse events will be obvious from the foregoing.

It is evident that if the nuts 123 are re-set, that the stroke of thepiston 63 will be varied because theaction of the moving piston on thefull-stroke valve is effective at a different period of piston movement,that is, on the outgoing stroke. 4 f

The pumping action by means of the engine E is then continuouslyautomatic as long as certain other events, to be described,

ceases to operate because grease cannotbe ejected with the normal airpressure available. It the line is opened of course grease can pass andthe air engine automatically commences operation and continues operationuntil said line is again closed. There is no dead point from which theoperation of the engine could not `be started. It the engine isexhausting when valve V is closed the spring 73 continues forcing the`,piston toward the head 71, in so tar as the rearward action of plunger51, due to the check valve 29, is independent of conditions in line 49.The piston is then ready for forward travelj whenever the line 49 isopened to permit the predetermined air pressure in line 107 to taireeitect. The tact that the air'engine can be stopped'by closing valve Vdoes not imply that only low grease pressures are attainable in theoutlet line 139 leading from the valve, for it the saidwline 139 isconnected with nearly clogged bearings, ,several thousand pounds persquare inch of pressure may be brought to bear on the-obstruction withonly a nominal air pressure inV cylinder 55. 'lhis is due to the ratioot the diameters ot piston 63 and plunger 51. The closing ot valve Vhowever, resists the high pressure.

lEig. 5 indicates the complete assembly of the apparatus and illustratesin ,dotted lines how the delivery line '49 is laid away in the horns orclips 15 when not in use. The apparatus may be towed about by means otthe forward handle-bar 21, or carried by means et the upward handle 17.Movement from one air linesuch as line 107, to another lilre one isreadily accomplished merely by loosening one line and applying theother. No manually operable valves can be lett open. The device issimple in application in so far as there are only obvious operations tobe performed byan operator.

In view of the above, it is believed that the various features of thisinvention will be clear without'turther elaboration, and it will be seenthat with the apparatus -herein described, the several objects of theinvention are achieved and other advantageous results attained.

As many changes could be made in carrying out the above constructionwithout de- June, 1920.

parting trom the scope ot the invention, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative and not in a limiting sense.

I claim: v

1. The airfengine comprising a cylinder, a reciprocating piston thereinhaving a rod thereon reaching-through a retaining cylinder, a returnspring within said retaining cylinder on one side ot the piston tendingto press said piston in one direction, a Jr'ullstroke valve gear adaptedto pass compressed luid to and from the other side of the piston, fullstroke automatic means controlling the character of the movement of saidvalve gear to move it to its extreme positions, lost-motion connectingmeans between the valve gear and the piston, said connecting meansincluding means tor adjusting the piston stroke and means associatedwith said retaining cylinder tor maintaining alignment between thepiston and valve gear. y, 2. An auton'i'atically operable air enginecomprising a work cylinder having a longitudinal extension cylinder, apiston in said work cylinder and a piston rod therefor passing throughsaid extension cylinder, a return spring surrounding said piston rod andseating in said extension cylinder, a driving stem joined to saidpiston' and passing trom the work cylinder, means on the extensioncylinder tor slidably supporting said stem, a valve including a valvestem adapted to permit passage ot air to and from one side of the pistonand operable by a bracket connecting said driving stem and said valvestem, whereby positive alignment between the piston rod and said valvestems is maintained.

3. An air engine 'comprising a main cylinder, a reciprocating'pistontherein having a rod thereon, an extension cylinder joined with saidmain cylinder, said rod passing through the extension cylinder, a returnspring within the extension cylinder and around said rod, tending topress said piston in one direction, a. valve gear admitting andreleasing air from the side of said piston opposite said spring, adriving stem joined to and moving with said piston and positioned formovement outside of said cylinders, portions associated with saidcylinders guiding said stem to prevent rotative movement ot' the stem,piston and rod, and driving means interposed between the driving stemand said valve gear.

In testimony whereof, I have signed my name to this specification this23rd day of raamt s. saints.

